THE ASSESSMENT OF THE SEASONAL PHYTOCHEMICAL COMPONENTS, ANTIMICROBIAL AND TOXICITY ACTIVITY OF HYDROALCOHOLIC LEAF EXTRACTS OF E. FLORIDA USED IN BRAZILIAN FOLK MEDICINE

• DOI: https://doi.org/10.22533/at.ed.813482417121

• Palavras-chave: Eugenia florida, phytochemical screening, antimicrobial activity, absence of mutagenicity, DPPH-Radical scavenging, NMR.

• Keywords: Eugenia florida, phytochemical screening, antimicrobial activity, absence of mutagenicity, DPPH-Radical scavenging, NMR.

• Abstract:

  Eugenia florida DC., Myrtaceae, is used in folk medicine for gastrointestinal diseases, although its biological activities have rarely been studied. The goal of this study is to assess the seasonal phytochemical components, antimicrobial activity, and toxicity effects of hydroalcoholic leaf extracts of E. florida (EEF) to provide a scientific basis for its use. Phytochemical screening and Thin Layer Chromatography (TLC) profiling of EEF confirmed the presence of various phytochemicals, such as flavonoids, triterpenoids, saponins, and steroids. Total phenolic content (TPC) was assessed using the Folin-Ciocalteu method to evaluate the presence and levels of phenolic compounds in each sample. The summer EEF exhibited the highest TPC value, 34.4 mg GAE/g, and showed good DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, with an average inhibitory concentration (EC50) of 16.03 mg/mL. The antimicrobial activity of EEF was evaluated against twelve bacterial species and three yeasts using the agar dilution and minimum inhibitory concentration (MIC) methods. In vitro antimicrobial activity demonstrated moderate inhibitory effects on Gram-positive bacteria such as Staphylococcus epidermidis and S. aureus (MIC 0.25 mg/mL). Mutagenic and toxicity activities were evaluated by the Ames mutagenicity assay in Salmonella typhimurium and the Artemia salina test. No mutagenic or toxic effects were observed in EEF. TLC analysis of triterpenoids revealed nine spots, with betulinic acid (BA) as the major compound, likely responsible for the biological activities described. BA was isolated by column chromatography and identified by spectroscopy and chromatographic methods (IR, NMR, and mass spectrometry). The presence of BA in the crude extract was quantified using high-performance liquid chromatography (HPLC). It can be concluded that E. florida leaves could be used in the treatment of bacterial gastroenteritis infections